Number of each character in a string

#this function takes in a string and returns the number of characters of each letter of the alphabet that are
#inside of the string
def my_function(my_string):
    
    #make the string lowecase for easier comparison
    lowercase_my_string = my_string.lower()
    
    #this list is used to keep track of the entire alphabet
    alpha_list = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"]
    
    #this list is used to be the comparator to the alpha_list and increment themselves from 0
    number_list = []
    for i in range(26):
        number_list.append(0)
    
	#this list is returned at the end and is a list of readable strings that will return in the format of
	#There are {number} {character}'s in this string.    
    number_in_alpha_list = []
    
    #this is the logic loop for the program, the first step is to loop through the provided string, easy enough
    for string_char in lowercase_my_string:
        
        #then for each character in the string we need to loop through the alphabet in the alpha_list
        for alphabet_char in alpha_list:
            
            #this is the complicated part, so we make a comparison from the character in the string to the character in the alphabet
            #and if they are equal, we increment the equivalent value in the number_list
            
            #for example: the first character called in my_function below is h, and h is at index 7 in the aplha_list
            #so we increment number_list[7] = 1
            if string_char == alphabet_char: number_list[alpha_list.index(alphabet_char)]+=1
    
    #Apparently there is no way to keep track of the index in a normal for loop, so I had to use this enumerate function to keep track of the index
    #it does the exact same thing as a for loop, but also keeps track of the index which is critical to getting the correct character out of the alpha_list
    
    
    for index, num in enumerate(number_list):
        if num > 0: 
            if num == 1:
                number_in_alpha_list.append("There is {number} {character} in this string".format(number = num, character = alpha_list[index]))
            else:
            	number_in_alpha_list.append("There are {number} {character}'s in this string".format(number = num, character = alpha_list[index]))
    
    #and at the end we return the list of strings and we can do what we wish with that list when we return it, I just print it out
    return number_in_alpha_list
	
print my_function("hello devin");

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